U.S. Defense Secretary Ash Carter says the United States will send an additional 560 soldiers to northern Iraq to take part in the fight against so-called Islamic State (IS) militants.

Speaking during a visit to Baghdad on July 11, Carter said the fresh forces would help to establish a combat staging hub for the long-awaited battle to recapture the northern city of Mosul from IS militants.

He said the staging hub is being set up at the Qayara Air Base -- a military installation near Mosul that had been captured by IS militants in 2014 but was retaken on July 9 by Iraqi government forces.

The additional U.S. troop deployment will raise the number of U.S. soldiers in Iraq to about 4,650.

IS overran large areas of northern and western Iraq in 2014.

Since then, Iraqi forces have regained significant swaths of territory with the backing of U.S.-led air strikes, training, and other assistance.